Here is the License for Corel X-3's use of there Clipart. I would guess that most major companies have a similar License for there products. I am not looking to join the argument but had this handy and thought I would post it.
2. COREL GUIDELINES FOR THE USE OF CLIPART, STOCK PHOTO IMAGES AND SAMPLE CONTENT:
Corel products may contain numerous clipart, photo images and sample content such as forms, templates, Paint Shop Pro “tubes” or similar items (collectively referred to as the "Images") which are either owned by Corel or licensed from a third-party. As a user of Corel products you are free to Use, modify and publish the Images as you wish subject to the restrictions set out below. If you are uncertain as to whether your intended Use is in compliance with the Guidelines set out below, Corel recommends that you seek the advice of your own attorney or legal counsel. Corel will not provide you with an opinion as to whether your Use is in compliance with these Guidelines.
2.1 YOU MAY, subject to any restrictions set out in Sections 2.2 and 2.3 below:
(i) incorporate any Image(s) into your own original work and publish, display and distribute your work in any media, provided you include a copyright notice in your work reflecting on the copyright ownership of both you and Corel as follows:
"Copyright (c) 200__ [your name] and its licensors. All rights reserved."; and
(ii) make one (1) copy of the Image(s) for backup or archival purposes.
2.2 YOU MAY NOT:
(i) resell, sublicense or otherwise make available the Image(s) for Use or distribution separately or detached from a product or web page. For example, the Image(s) may be Used as part of a web page design, but not be made available for downloading separately or in a format designed or intended for permanent storage or re-use by others;
(ii) provide the Image(s) to third parties or permit the Use of the Image(s) by third parties separately or as part of any other product, however, third parties may be provided with copies of the Image(s) (including digital files) as part of a work product;
(iii) create scandalous, obscene, defamatory or immoral works using the Image(s) nor Use the Image(s) for any other purpose which is prohibited by law;
(iv) Use or permit the Use of the Image(s) or any part thereof as a trademark or service mark, or claim any proprietary rights of any sort in the Image(s) or any part thereof;
(v) Use any of the Images which contain identifiable individuals or entities for any commercial purpose including, without limitation, in a manner which suggests their association with or endorsement of any product or service;
(vi) Use the Image(s) in electronic format, on-line or in multimedia applications unless the Image(s) are incorporated for viewing purposes only and no permission is given to download and/or save the Image(s) for any reason;
(vii) rent, lease, sublicense or lend the Image(s), or a copy thereof, to another person or legal entity. You may, however, transfer all your license to Use the Image(s) to another person or legal entity, provided that (i) you transfer the Product, including the Image(s), and this License, including all copies (except copies incorporated into your work product as permitted under this License), to such person or entity, (ii) that you retain no copies, including copies stored on a computer or other storage device, and (iii) the receiving party agrees to be bound by the terms and conditions of this License; or
(viii) Use any Image(s) except as expressly permitted by this License.